To play ordinary 2D tetris well, you have to learn to recognize chiral variants (such as the ones below) from one another.

_____
|.....|
|.....|
_____
|.....|
|.....|
_____ _____
|.....||.....|
|.....||.....|

_____ _____
|.....||.....|
|.....||.....|
_____
|.....|
|.....|
_____
|.....|
|.....|

You can't simply match them up by rotating them in the plane. However, in existing 3D tetris (such as BlockOut) you can easily substitute one with another by rotating this shape through the 3rd dimension.

Unfortunately, there are also chiral 3D shapes that cannot be matched up against each other by rotating them in 3-dimensional space (e.g., left screw tetracube / right screw tetracube), but can be matched by rotating them through the 4th dimension.

Fortunately, we have tools to do that: mirrors, and hence the idea:

A 3D tetris, with mirror side walls. By pushing your brick onwards to the wall, you obtain a mirror image of the brick from the alternate virtual reality, and you're in business.
-- Inyuki, Jun 06 2012

BlockOut http://en.wikipedia.org/wiki/Blockout
The 3D Tetris. [Inyuki, Jun 06 2012]

BlockOut forum http://www.blockout...d=1147&catid=2#1147
Well, just added the idea to BlockOut forum, as a feature request. [Inyuki, Jun 06 2012]

Kata/Ana AlterDimension games Kata_2fAna_20Alter-Dimension_20Games
Covers 4D games - I love this concept! [bungston, Jun 06 2012]

I like it. Great for introducing chirality; make students play this for 15 minutes before their first lectures on chirality and I think they'd get it.
-- imagin8or, Jun 06 2012



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